Section-insulator for overhead electric conductors



2 SheetsSheet 1.

(No Model.)

B. THOMSON. SECTION INSULATOR FOR OVERHEAD ELBOTRIG'OONDUGTORS. No.434,961.

Patented Aug. 26, 1890 l/VVE/VTOR ELIHLJ THUMEUN- WITNESSES:

ATTORNEYS (No Model.) 2 Sheets-Sheet 2.

E. THOMSON. SECTION INSULATOR FOR OVERHEAD ELECTRIC GONDUGTORS. No.434,961. Patented Aug. 26, 1890.

C; A O

WITNESSES: l/VVE/VTOR I ELIHLI THuM5u l 7/. f/ u ATTORNEYS UNITED STATESPATENT OFFICE.

ELIHU THOMSON, OF LYNN, MASSACHUSETTS, ASSIGNOR TO THE THOMSON- HOUSTONELECTRIC COMPANY, OF CONNECTICUT.

VSE CTION-INSULA TOR FOR OV E RHEAD ELECTRIC CONDUCTORS.

SPECIFICATION forming part of Letters Patent No. 434,961, dated August26, 1890. Application filed March 10, I890. Serial No. 343,386. (Nomodel.)

To all whom it may concern.-

Be it known that I, ELIHU THOMSON, a citizen of the United States,residing at Lynn, in.

the county of Essex and State of Massachusetts, have invented certainnew and useful Improvements in Section-Insulators for Overhead ElectricConductors, of which the followlng is a specification.

My invention consists in an improved constructlon of a support foroverhead lines as by the trolley-wheel leaving one section and passingto the other, will be automatically extinguished.

The invention is illustrated in the drawings, in which Figure 1 is aside view of the same. Fig. 2 is a plan, and Fig. 3 shows itsapplication to an overhead electric-railway line in the manner proposed.

In Fig. 1 E E are two ears, shaped as shown, to which the line-conductorcan be attached on the under side by soldering or other suitable manner,the end of the line being drawn up through holes H H provided for thepurpose, and the ends riveted to retain the same in position. The ears EE are extended toward each other along the line of travel in the samehorizontal plane and project to within a short distance of each other,being separated by a small air-space S, Figs. 1 and 2. These extensionsform a way for the trolley-wheel after leaving the trolleywire properandfeed-current to the car. The airspace S is narrowest at its lowerportion and becomes wider and wider toward the top. The cars E E aresupported on a frame F, extending back of projections P of the ears E E,and secured thereto by bolts B, the frame F being, however, safelyinsulated from the projections P of the ear E by the interposition ofsuitable insulating material I, such as sheets of mica fiber or othergood insulating material. It is not necessary, of course, that the frameshould reach back of the projections P, as they might of course be onthe inner sides; but this is the preferred arrangement for mechanicalreasons. The insulation I is also extended along the bolts B. Whileunder favorable conditions as to weather, or the employment of acomparatively low potential on the overhead line, the insulation thusprovided might prove sufficient, it is preferred in the employment ofpotentials as high as three hundred to five hundred volts and upward tofurther increase the insulating effect by pitching over the ears E E andframe F, where they are bolted together, with a goodinsulating-pitch-such as asphaltumand wrapping the whole with a pitchedtape, or a tapefree of pitch maybe wound about these parts and the wholethen soaked in or painted with pitch. This will effectually prevent anyleakage occurring by moisture gaining access to the joints and reducingthe resistance inwetand rainy weather. 7

It is even advantageous in most cases to tape the frame F from one sideto the other, as indicated in Fig. 1, so that leak of current from onesection of conductor to the other over dampened or moist surfaces isabsolutely prevented. Hoods B B may also be used to shed water off thejoints between the frame F and the ears E E, though it is not absolutelynecessary that these be provided in all instances if the taping andpitching in the manner described be thoroughly and efiectuallyperformed.

The divergence of the sides of the space S, as shown in Fig. 1, is todestroy any are that might be established by the trolley-wheel in 8 5passing from one section of conductor to the next. The are soestablished will rise to the upper and wider portion of the space S onaccount of the current of air established by the heated flame, and Willbe bowed and eventu- 9o The section-insulator itself is best support-Fig. 3 shows theapplicat-ion of such 5 ed as shown in Fig. 3that is, thecross or s de suspension wires Ware attached to each side of the frameF, respectively. The strain of the cross-Wires will then counteract thestrain of the overhead conductor 0 O (3", which of course tend toelongate the frame F of the insulator, and would destroy its usefulnessfor the purpose intended were it not made exceptionally strong; but, byattaching the cross-wires W in the manner mentioned, the frame F, and,in fact, the whole insulated structure, can be made much lighter overWhat it would otherwise be necessary to make it. The structure, whensupported in this manner, therefore can be made to presentaneaterappearance and can be made more compact, more efficient, and itsthorough insulation is accomplished with greater ease.

The feeding of current to any section of the overhead conductor, as C,is accomplished by feed-wires Vt, these Wires being preferably attachedat such points along the conductor vC as will equalize the potentialthroughout its length. Thus if one feeder were used, it would beattached at the center of the conductor C; if two were employed, atone-quarter of the distance from the end, and so on. Switches S are ofcourse provided to each feed-wire W, so that in case it is desired ornecessary to cut out a section,as 0, along the track-as when a fireoccurs or for any other reasonit is only necessary to open the swltch S,when such section willbeidle, while cars may still be operated on theadjacent sections 0 C".

What I claim as new, and desire to secure by Letters Patent, is;

1. In a connector forline-conductorson electric railways, thecombination of two cars attached to the two ends of the line-sections,respectively, and an open metallic frame connectingthe said ears, butinsulated therefrom, thesaid frame sustaining the ears so as to providean air-space between their ends and around them.

2. In a connector for line-conductors on electric railways, thecombination, with two ears adapted to be attached to ad j acent'ends ofthe line-wires, of an open frame extending laterally and forming aninsulated mechanical connection between the two ears.

3'. In a connector for electric line-wires, the combination, with twocars adapted to be attached to adjacent ends of the line-wire, butseparated by an air-space, of an open frame forming an insulatedmechanical connection between the two ears,but leavingafree space abovethe opening between the two ears.

4. The combination, with the two cars adapted to be attached to adjacentends of an open sectional line-conductor, of a connecting-frameconnected to each of said-ears through insulation, and a protecting-capfor the insulation at each point of connection.

5. The combination, with ears E E, of an open connecting-frame coveredwith insulation.

6. The combination, with the ears E E, of a frame forming an insulatedmechanical connection between the said ears, the said frame and thejoints between the frame and the'ears being covered with insulatingmaterial.

7. The combination, with a connector for adjacentsectionsotline-conductor consisting of two ears attached to the adjacent ends ofthe wire and a connecting-frame therefor, of

supporting-wires connected to the said frame and extendin gtransversely.

8. The combination, with a connector for sectional line-wires consistingof ears attached to adjacent ends of two wire sections and connected bya diamond-shaped frame, of transverse supporting-wires attached toopposite angles of the said frame.

9. The combination, with a sectional lineconductor, of connectorsconsisting of two ears attached to the ends of adjacent sectionsseparated by a free air-space, and a supply-wire connecting each of saidsections to a main feed-wireQ ELIHU THOMSON. Witnesses: 1

JOHN W. GIBBONEY, WINIFRED J. PLUMSTEAD.

